That’s a question that probably requires more digging than I want to do.

On the DNS side, it depends on CNAME record types. Sources in the Wikipedia article suggest that was defined in 1987 and updated in 1997.

On the server side, it depends on how easily the server software can be configured to use multiple domains for the same site (or how easy it is to set up a redirect). This sounds like a deep home to research, and I’m not going to bother. But cPanel and Webmin are both about 30 years old now.